<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <script src="jquery-3.7.1.min.js"></script>
</head>
<body>

<table>
    <tr class="trclass">
        <td>12345</td>
        <td>abcde</td>
        <td>67890</td>
    </tr>
</table>


<button id="btnadd">add row</button>

<script>

    var msg1 = "china";
    var msg2 = "usa";
    var msg3 = "russia";

    $("table").on('click', '.trclass', function () {
        console.log($(this)[0])
    })

    $("#btnadd").click(function () {
        $("table:first tbody").append(` <tr class="trclass">
            <td>${msg1}</td>
            <td>${msg2}</td>
            <td>${msg3}</td>
        </tr>`);

        // $("table:first tbody").append(" <tr class='trclass'>< td > " + msg1 + " < /td><td>" + msg2 + "</td> <td>" + msg3 + "</td> </tr>");
    })
</script>
</body>
</html>